A fishy smell from the vaginal area is almost always caused by an overgrowth of certain bacteria, and the fastest way to get rid of it depends on what’s driving that overgrowth. In most cases, the odor comes from a common condition called bacterial vaginosis (BV), which produces specific chemicals (dimethylamine and trimethylamine) as bacteria break down compounds in vaginal discharge. Some steps can reduce the smell within hours, but fully eliminating it typically requires treatment that takes five to seven days.
Why It Smells Fishy in the First Place
Your vagina naturally contains a balance of bacteria, with beneficial species keeping the environment slightly acidic (a pH below 4.5). When that balance shifts and less helpful bacteria take over, they produce volatile amines, the same type of compounds responsible for the smell of rotting fish. Additional byproducts like putrescine and cadaverine can make the odor stronger. This bacterial shift is what clinicians call bacterial vaginosis, and it’s the most common vaginal infection in people of reproductive age.
BV isn’t a sexually transmitted infection, though sexual activity can trigger it. It can also develop after antibiotic use, hormonal changes, or anything that disrupts your vaginal pH. The hallmark signs are a thin, milky-white discharge, a vaginal pH above 4.5, and that unmistakable fishy smell, which often gets stronger after sex or during your period.
What You Can Do Right Now
If you need to reduce the odor quickly while you figure out next steps, a few things help within hours:
- Rinse with warm water only. Gently wash the external vulva with plain warm water. Soap, even mild soap, can further irritate the area and worsen the bacterial imbalance. Pat dry thoroughly afterward.
- Change into clean, breathable underwear. Cotton or moisture-wicking fabrics reduce the warm, damp conditions that help odor-causing bacteria thrive. Research on breathable materials shows they prevent the 1°C temperature increase that non-breathable fabrics create in the genital area.
- Try an over-the-counter vaginal pH gel. Products containing lactic acid or similar buffering agents are designed to lower vaginal pH back toward the acidic range where beneficial bacteria can recover. These can reduce noticeable odor for up to three days per application and are available at most pharmacies without a prescription.
These measures manage the symptom, not the cause. They’re useful for getting through a workday or a social event, but they won’t resolve BV on their own.
The Treatment That Actually Resolves It
BV requires antibiotics to fully clear. The CDC’s current treatment guidelines recommend a seven-day course of oral antibiotics taken twice daily, or a vaginal antibiotic gel applied once daily for five days, or a vaginal antibiotic cream used at bedtime for seven days. All three options have similar effectiveness.
Most people notice the smell fading within two to three days of starting treatment, though it’s important to finish the full course even after the odor is gone. Stopping early increases the chance of recurrence, and BV is already prone to coming back: roughly half of people who get it will have another episode within 12 months.
You’ll need a healthcare provider to prescribe these treatments. Many clinics and telehealth services can diagnose BV based on your symptoms and a simple test, so you don’t necessarily need an in-person exam.
Boric Acid Suppositories
Boric acid vaginal suppositories are an over-the-counter option that some people use alongside or after antibiotic treatment. The standard approach is a 600-milligram suppository inserted vaginally once daily for 7 to 14 days. Cure rates in clinical studies have ranged widely, from 40% to 100%, depending on the condition being treated and the study design. Boric acid is more commonly studied for recurrent yeast infections than for BV specifically, but some providers recommend it as a supplemental therapy for persistent BV odor.
These suppositories are for vaginal use only and should never be taken orally. They’re also not safe during pregnancy.
What Makes the Smell Worse
The single biggest mistake is douching. It feels logical to wash away the odor from inside, but douching consistently makes things worse. Research shows that women who douche within seven days before testing are more than twice as likely to have BV. Those who douche daily have BV rates of 32%, compared to 24% among occasional douchers. Douching also increases the risk of pelvic inflammatory disease by roughly 73%, which can lead to chronic pain and fertility problems.
Researchers describe this as a “harmful cycle”: women wash to reduce itching, odor, and discharge, only to develop more significant symptoms from the disruption to their normal bacterial balance. Scented feminine washes, sprays, and wipes follow the same pattern. They mask the odor briefly while making the underlying problem worse.
Keeping the Smell From Coming Back
After treatment clears the infection, the goal is restoring and maintaining a healthy vaginal microbiome. A few evidence-based strategies help:
Vaginal probiotics containing Lactobacillus crispatus, the dominant beneficial species in a healthy vagina, are being actively studied as a follow-up to antibiotic treatment. Clinical trials are testing vaginal tablets containing billions of these bacteria, taken for seven days after completing antibiotics, to see if they prevent BV from returning. While the results aren’t final, the science behind the approach is sound: reintroducing the bacteria that maintain an acidic, protective environment.
Day-to-day habits matter too. Wearing breathable fabrics, sleeping without underwear to allow airflow, avoiding scented products in the genital area, and changing out of sweaty workout clothes promptly all help keep conditions unfavorable for the bacteria that produce fishy odors.
When It’s Not BV
A fishy smell can also come from trichomoniasis, a sexually transmitted infection caused by a parasite. The key difference is the discharge: trichomoniasis typically produces a yellow-green, sometimes frothy discharge, along with pain during urination or sex. BV discharge tends to be thinner and grayish-white. Trichomoniasis requires a different antibiotic, so getting the right diagnosis matters.
Less commonly, a forgotten tampon or other retained object can produce an intense fishy or rotten smell that comes on suddenly. This resolves immediately once the object is removed, though you may need a provider’s help if you can’t reach it yourself. A strong, sudden odor that doesn’t match your usual patterns is worth having evaluated promptly.